A technique of spatially modulating illumination light can be cited as an example of a technique of performing super-resolution observation of an observation object such as a biological specimen. For example, the technique of spatially modulating illumination light is described in Japanese Patent Application Laid-Open No. 11-242189 (Patent Document 1), U.S. Reissued Patent No. 38307 (Patent Document 2), W. Lukosz, “Optical systems with resolving powers exceeding the classical limit. II”, Journal of the Optical Society of America, Vol. 37, PP. 932, 1967 (Non-Patent Document 1), and W. Lukosz and M. Marchand, Opt. Acta. 10, 241, 1963 (Non-Patent Document 2).
In these techniques, a spatial frequency of a structure of the observation object is modulated with the spatially modulated illumination light, and information on the high spatial frequency exceeding a resolution limit is caused to contribute to image formation of a microscope optical system. However, in order to observe a super-resolution image, it is necessary to demodulate a modulated image of the observation object (modulated image). The demodulation method is mainly fallen into optical demodulation (see Non-Patent Document 1 and 2) and computing demodulation (see Patent Documents 1 and 2). The optical demodulation is realized by re-modulation of the modulated image with a spatial modulation element such as a diffraction grating.
Patent Document 1: Japanese Patent Application Laid-Open No. 11-242189
Patent Document 2: U.S. Reissued Patent No. 38307
Non-Patent Document 1: W. Lukosz, “Optical systems with resolving powers exceeding the classical limit. II”, Journal of the Optical Society of America, Vol. 37, PP. 932, 1967
Non-Patent Document 2: W. Lukosz and M. Marchand, Opt. Acta. 10, 241, 1963
However, the computing demodulation takes time because of complicated arithmetic processing, and the observation object is hardly observed in real time. On the other hand, the optical demodulation does not take much time because of the use of the spatial modulation element such as a diffraction grating. However, because demodulation accuracy depends on shape accuracy and arrangement accuracy of the spatial modulation element, a good super-resolution image is hardly obtained.
For example, in the demodulation method (optical demodulation) described in Non-Patent Document 2, an optical path for the modulation and an optical path for the demodulation are provided in parallel, and different portions of the common diffraction grating are used in the modulation and the demodulation, thereby improving the problem of the arrangement accuracy. However, unfortunately an observation field is extremely narrowed because a pupil of the optical system relating to the modulation and a pupil of the optical system relating to the demodulation cannot be conjugated.
In view of the foregoing, a problem of the invention is to provide a microscope apparatus which can produce the information on the super-resolution image in short time and an image processing method in which the super-resolution image can be obtained with the microscope apparatus.